Yes a bolt and spacer would work...never thought of that when I broke my tool...Do you need the tool?
Wouldn't a bolt with spacer work?
I have the same concern about galling but, I wanted to use the SST riv-nuts as it is easier to replace a rusted fastener that it is a rusted riv-nut. I am going to try the SST fasteners and if I experience galling then I am going to revert to a black oxide coated fastener and replace them as they show rust.This is a great mod for these sleds,I've done several. I use the zinc rivnuts with stainless fasteners with no rust problems.
Stainless rivnuts and stainless fasteners together scares me a bit....galling.